Volume indicator for fluid tanks

ABSTRACT

A fluid volume indicator for tanks having a follower, the position of which is directly proportional to the volume of the fluid in the tank and a visible indicator between the follower and a fixed wall, the indicator being movable along the axis of the follower and being acted upon by the two opposed helical compression springs, one between the indicator and the follower and the other one between the indicator and the fixed wall of the tank so that the movement of the indicator is proportional to the movement of the follower.

131-290. O7=-l8-72 XR 3967711220 .'-';.v ...;;;;.e -.-;I...; Ostwald eta]. [4 1 Jul 18 1972 [54] VOLUME INDICATOR FOR FLUID 1,624,659 4/1927Eynon ..73/299 TANKS iiZiZl 32322 5 1; 153 92 rnit 5 X [72] Inventors:Fritz oStWllld, Buchschlag; Siegfried Her- 429 29 2 19 9 I kelste'bach'Germany 3,451,420 6/1969 Bullivant... .....137/403 3 Assignee; ITTIndustries, Inc New york, 3,489,169 1/1970 Stein 137/403 [22] Filed:June 1970 Primary Examinen-bouis J. Capozi [211 App! NOJ 43,885AttorneyC. Cornell Remsen, Jr., Walter J. Baum, Parr] W. Hemmmger,Charles L. Johnson, Jr., Philip M. Bolton, Isidore [30] F A u 6 m t D taTogut, Edward Goldberg and MenottiJ. Lombardi, Jr.

orergn pp ca on 011 y a June 6, 1969 Germany ..P 19 28 850.7 ABSTRACT Afluid volume indicator for tanks having a follower, the posi- [52] U.S.Cl ..1l6/1 18, 73/290, 737/2959, tion of which is directly proportionalto {he volume of the fluid I ig g in the tank and a visible indicatorbetween the follower and a [51] lnt.C 299 4/19 fixed wall the indicatorbeing movable along the axis of the [58] held 3 9 follower and beingacted upon by the two opposed helical compression springs, one betweenthe indicator and the follower and the other one between the indicatorand the fixed [56] References Cited wall of the tank so that themovement of the indicator is pro- UNITED STATES PATENTS portional to themovement of the follower. 794,676 7/1905 Martin ..73/320 7 Claim, 3Drawing Figures 2. tt TIRE 24 VOLUME INDICATOR FOR FLUID TANKSBACKGROUND OF THE INVENTION 1. Field of the Invention This inventionrelates to volume indicators for fluid tanks.

2. Description of Prior Art There are a variety of devices available forexternally indicating the amount of fluid within a tank. The tank may beeither a gas pressure tank with a movable wall such as a piston or itmay be a liquid tank in which case the indicating device measures theliquid level. The liquid level indicating devices usually have a floatof some type which follows the liquid level with the movement of thefloat being mechanically transmitted to an external indicator. This typeof construction is shown in U.S. Pat. Nos. 41,620, 794,676, and2,371,511.

SUMMARY OF THE INVENTION It is an object of the present invention toprovide a volume indicator which may be adapted to either a liquid orgas tank to indicate the fluid volume within the tank.

It is a further object of this invention to provide a volume indicatorfor fluid tanks which is simple, reliable, lightweight, and which doesnot greatly increase the space required for the tank.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a partial longitudinalsectional view of a volume indicator constructed in accordance with thisinvention.

FIG. 2 is a cross section taken along line 22 of FIG. 1 with theindicating sleeve and helical spring omitted for clarity.

FIG. 3 is an elevational view looking at slot 7 of FIG. 2.

DESCRIPTION OF THE PREFERRED EMBODIMENT This invention achieves theseobjects by providing a fluid volume indicator for tanks having afollower, the position of which is directly proportional to the volumeof fluid in the tank and a visible indicator between the follower and afixed wall, the indicator being movable along the axis of the followerand being acted upon by the two opposed helical compression springs, onebetween the indicator and the follower and the other one between theindicator and the fixed wall of the tank so that the movement of theindicator is proportional to the movement of the follower. The springbetween the follower and the indicator has more turns than the springbetween the indicator and the fixed wall but in all othercharacteristics and dimensions they are the same. In this manner it ispossible to indicate large movements of the follower with relativelysmall indicator movement.

Referring now to the attached drawings there is shown one end of a gaspressure tank 20 and a fluid level follower I having disk 2 connected toone end thereof. Follower l is adapted to move in a longitudinaldirection within the cylindrical extension 3 oftank 20. Disc 2 is in asealed, slidable engagement within the inner surface of extension 3.Follower l is moved by a piston 21 disposed in tank 20 secured bysoldering, welding or the like to follower 1 adjacent the other endthereof. Piston 21 is in a sealed, slidable engagement with the innersurface of tank 20 to fonn a movable wall in tank 20 so that themovement of the follower l is proportional to the fluid volume in thetank 20. A tank cover 4 is provided with an axial extension 5 having abore 22 which is coaxial with the follower 1. One

side of the axial extension 5 is cut away to provide a longitudinalviewing slot 7. A glass tube 6 inserted in the bore 22 provides a meansfor viewing the movement of an indicator 14 within the glass tube 6. Theglass tube 6 is held in the extension 5 by means of an annular clampingplate 8 which is fixed to the under side of the cover 4 and a recess 23formed in fixed end wall 24 ofextension 5.

The follower I contains a longitudinal bore 9 which is coaxial with thebore 22 in extension 5. A cup-shaped spring support I is fitted withinbore 9 and attached to the front of disc 2. A guide rod 11 includes onone end thereofdisc I6 which is attached to the inner surface of endwall 24 by soldering, welding or the like to thereby secure one end ofguide rod 11. Guide rod 11 extends along the length of and coaxial tobores 9 and 22 and is supported in a sliding relationship at the otherend thereof by the cup-shaped spring support 10. Indicator [4 in theform ofa tube is disposed to encircle guide rod 11 in a coaxialrelationship and is movable along rod 11. Indicator 14 includes aninwardly directed end wall portion 15 slidably engaging rod 11, theupper edge ofthe wall portion 15 providing a reference line 27 forindicator 14. This is only one way a necessary reference line could beprovided on indicator 14. The reference line could be in the form of avisible mark at any point along the outer surface of indicator 14 inregistry with slot 7. A first helical spring 12 acts between the springsupport 10 and one side of wall portion 15 and a second helical spring13, which is similar to the spring 12 except for being much shorter,acts between the other side of wall portion 15 and disc 16. Except forthe number of turns, the springs 12 and 13 are identical incharacteristics and dimensions.

A cross bore 17 in the follower l and the opening 18 in the springsupport 10 connect the chambers 25 and 26 to the interior of tank 20.

The surface 19 on the cover extension 5 is provided with graduationswhich together with reference line 27 on indicator 14 provides anindication of the volume of fluid within the tank 20.

As the volume of fluid within the tank changes, the follower 1 moves inan axial direction. The indicator 14, which is trapped between thesprings 12 and 13, moves in proportion to the movement of thefollower 1. However, due to the fact that the spring 12 has more turnsthan the spring 13, the movement of the indicator 14 is much less thanthe movement of the follower 1.

The movement of the indicator l4 and, hence, reference line 27 isvisible through glass tube 6 and may be measured by means of thecalibrated scale on the surface 19.

We claim as our invention:

1. A volume indicator for a fluid tank comprising a first longitudinalextension of said tank extending along a given axis;

a follower disposed coaxially of said given axis within said firstextension and extending into said tank to enable said follower to bemoved along said given axis by the fluid content of said tank, theposition of said follower being directly proportional to the volume offluid in said tank;

a first longitudinal bore disposed within said follower coaxially ofsaid given axis;

a cup-shaped support disposed within said first bore coaxially of saidgiven axis and secured to one end of said follower;

a cover for said first extension, said cover including a secondlongitudinal extension disposed coaxially of said given axis, saidsecond extension including a second longitudinal bore disposed withinsaid second extension coaxially of said given axis and aligned with saidfirst bore;

a rod disposed coaxially of said given axis extending from a fixed endwall of said second extension through said second bore into said firstbore to a position beyond said cup-shaped support, said rod beingsupported by said fixed end wall and said cup-shaped support;

a glass tube disposed coaxially of said given axis in said second boreencircling said rod but radially spaced from said rod;

an indicator in the form of a tube disposed coaxially of said given axisin said second bore between said rod and said glass tube, said indicatorincluding an inwardly turned end wall slidably engaging said rod and areference line;

a longitudinal slot formed in said second extension to expose saidindicator and said reference line through said glass tube;

a first spring disposed coaxially of said given axis and encircling saidrod extending from said cup-shaped support to the adjacent side of saidinwardly turned end wall;

a second spring disposed coaxially of said given axis and encirclingsaid rod extending from said fixed end wall to the adjacent side of saidinwardly turned end wall; and

a calibrated scale disposed adjacent said longitudinal slot whichtogether with said reference line indicates the volume of the fluidwithin said tank;

said indicator being moved proportional to the movement of said followerby the cooperative arrangement of said follower, said fixed end wall,said cup-shaped support and said first and second springs.

2. A volume indicator according to claim 1, wherein said first andsecond springs are each a helical compression spring.

3. A volume indicator according to claim 1, wherein the number of turnsand the length of said first spring is greater than the number of turnsand the length of said second spring and all other dimensions andcharacteristics of said first and second springs are the same.

4. A volume indicator according to claim 1, wherein said followerincludes a piston connected to that end of said follower disposed insaid tank and in a slidably sealed relation with the inner wall of saidtank to enable said follower to be moved by the fluid content of saidtank.

5. A volume indicator according to claim 1, wherein said glass tube isheld in said second extension by means of a recess in the inner surfaceof said fixed end wall holding one end of said glass tube and an annularclamping plate secured to said cover adjacent the end of said firstextension and holding the other end of said glass tube.

6. A volume indicator according to claim I, further including a radialbore disposed in said follower adjacent the end thereof within said tankbetween said first bore and said tank, and

an aperture in said cup-shaped support to provide fluid communicationbetween said tank, said first bore and said second bore.

7. A volume indicator according to claim 1, wherein said followerincludes a disc extending radially from an end of said follower adjacentsaid cover in a slidable relationship with the inner surface of saidfirst extension; and

said cup-shaped support is secured to a transverse surface of said discadjacent said cover and extending along said given axis toward saidtank.

1. A volume indicator for a fluid tank comprising a first longitudinalextension of said tank extending along a given axis; a follower disposedcoaxially of said given axis within said first extension and extendinginto said tank to enable said follower to be moved along said given axisby the fluid content of said tank, the position of said follower beingdirectly proportional to the volume of fluid in said tank; a firstlongitudinal bore disposed within said follower coaxially of said givenaxis; a cup-shaped support disposEd within said first bore coaxially ofsaid given axis and secured to one end of said follower; a cover forsaid first extension, said cover including a second longitudinalextension disposed coaxially of said given axis, said second extensionincluding a second longitudinal bore disposed within said secondextension coaxially of said given axis and aligned with said first bore;a rod disposed coaxially of said given axis extending from a fixed endwall of said second extension through said second bore into said firstbore to a position beyond said cup-shaped support, said rod beingsupported by said fixed end wall and said cup-shaped support; a glasstube disposed coaxially of said given axis in said second boreencircling said rod but radially spaced from said rod; an indicator inthe form of a tube disposed coaxially of said given axis in said secondbore between said rod and said glass tube, said indicator including aninwardly turned end wall slidably engaging said rod and a referenceline; a longitudinal slot formed in said second extension to expose saidindicator and said reference line through said glass tube; a firstspring disposed coaxially of said given axis and encircling said rodextending from said cup-shaped support to the adjacent side of saidinwardly turned end wall; a second spring disposed coaxially of saidgiven axis and encircling said rod extending from said fixed end wall tothe adjacent side of said inwardly turned end wall; and a calibratedscale disposed adjacent said longitudinal slot which together with saidreference line indicates the volume of the fluid within said tank; saidindicator being moved proportional to the movement of said follower bythe cooperative arrangement of said follower, said fixed end wall, saidcup-shaped support and said first and second springs.
 2. A volumeindicator according to claim 1, wherein said first and second springsare each a helical compression spring.
 3. A volume indicator accordingto claim 1, wherein the number of turns and the length of said firstspring is greater than the number of turns and the length of said secondspring and all other dimensions and characteristics of said first andsecond springs are the same.
 4. A volume indicator according to claim 1,wherein said follower includes a piston connected to that end of saidfollower disposed in said tank and in a slidably sealed relation withthe inner wall of said tank to enable said follower to be moved by thefluid content of said tank.
 5. A volume indicator according to claim 1,wherein said glass tube is held in said second extension by means of arecess in the inner surface of said fixed end wall holding one end ofsaid glass tube and an annular clamping plate secured to said coveradjacent the end of said first extension and holding the other end ofsaid glass tube.
 6. A volume indicator according to claim 1, furtherincluding a radial bore disposed in said follower adjacent the endthereof within said tank between said first bore and said tank, and anaperture in said cup-shaped support to provide fluid communicationbetween said tank, said first bore and said second bore.
 7. A volumeindicator according to claim 1, wherein said follower includes a discextending radially from an end of said follower adjacent said cover in aslidable relationship with the inner surface of said first extension;and said cup-shaped support is secured to a transverse surface of saiddisc adjacent said cover and extending along said given axis toward saidtank.